裂隙岩体深埋长隧洞断裂控水模型及突、涌水量多因素综合预测

FAULT-DOMINATED WATER MODEL AND MULTIFACTOR METHOD FOR PREDICTING WATER INFLOW AND INRUSH OF DEEP LONG TUNNEL IN FRACTURED ROCK MASSES

由于深埋长隧洞围岩的力学、水力学特性明显区别于浅埋隧洞,且深部岩体不易勘探,因此深埋隧洞突、涌水量预测难度较大。针对高地应力、高水力梯度和高地温等复杂的深部地质环境,结合南水北调西线工程,提出了以断裂控水模型为基础的多因素综合评判方法。该方法是以大型断裂带为主要地下水通道的宏观地质模型作为基础;再分别研究对突涌水有影响的各种深部地质环境因素的影响规律;最后对宏观模型估算的突、涌水量进行综合修正。该方法为评价深埋长隧洞突涌水和隧洞施工与防护提供一种新的思路。

The prediction of water inflow and inrush in deep tunnels is relatively difficult due to the mechanical and hydro-mechanical characteristics remarkably different from those in shallow tunels, and the difficulty in geological exploration as well. In respect to deep and complex geological environments, such as high initial geostress, high hydraulic gradient and high rock temperature, etc., a multifactor prediction method based on the fault-dominated water model has been proposed, in terms of the research work on West Route of South-to-North Water Transfer Project. Firstly, a macro geological model is adopted to preliminarily assess water inflow and inrush, mainly regarding large-scale faults as groundwater channels. Based on the effect laws of deep geological environment factors which have influence on water inflow and inrush, a series of coefficients are determined and utilized for the final modification of water inflow and inrush estimated by the macro geological model. The presented method can be employed for assessment of water inflow and inrush from deep long tunnels during tunnel construction and supporting.